65817881028 has 36 divisors (see below), whose sum is σ = 170242120048. Its totient is φ = 21429077040.

The previous prime is 65817881021. The next prime is 65817881029. The reversal of 65817881028 is 82018871856.

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (65817881021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21257458 + ... + 21260553.

Almost surely, 2^65817881028 is an apocalyptic number.

It is an amenable number.

65817881028 is an abundant number, since it is smaller than the sum of its proper divisors (104424239020).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65817881028 is a wasteful number, since it uses less digits than its factorization.

65817881028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42518064 (or 42518059 counting only the distinct ones).

The product of its (nonzero) digits is 1720320, while the sum is 54.

The spelling of 65817881028 in words is "sixty-five billion, eight hundred seventeen million, eight hundred eighty-one thousand, twenty-eight".